Chowdhury, 24, then raided Afzal's taxi office and stabbed him 20 times while she watched.

Riaz then hid the identity of the killer from investigators, and even wiped evidence of the messages proving she arranged it alongside Chowdhury from her phone, a jury heard.

Police investigating the case however came across messages between Riaz and Chowdhury, in which she told him: "You are my last resort".

Central News

Victim: Mohammed Yasser Afzal

Sandip Patel, prosecuting, told the court: "You may conclude that they planned secretly Mr Afzal's murder. Such a thing rarely happens without a reason.

"The evidence from their messages indicated she was profoundly unhappy with Mohammed Afzal because he threatened on occasion to expose their relationship including intimate photos of them to her family."

Riaz, a second year law student at City University in London, attempted to conceal her relationship with Mr Afzal because her parents did not approve of them being together, it was claimed.

A jury was told how Mr Afzal treated Riaz "like a Queen".

However by February 2014 the relationship had turned sour, and she was desperate to escape, the court heard.

Mr Patel explained: "She wanted to end the relationship but was concerned he would blackmail her and reveal details of their physical relationship to her mother."

She is accused of setting up the killing alongside Chowdhury, an old boyfriend who had recently spent time in prison.

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Murderer: Gulam Chowdhury killed Afzal

Mr Patel told jurors: "Shortly after his release from prison they rekindled their relationship and from which sprouted their desire to eliminate Mr Afzal, a word which was used by Nargis Riaz in a text message."

After Riaz asked him for a favour, Chowdhury, a devout Muslim, texted her: "I am willing to burn in hell for you, I swear."

Riaz later replied: "How would I live with myself knowing I got you to do the ultimate?"

Although she later have a change of heart and backed away from the plan, "her indecision was short lived," said Mr Patel.

On March 24, Riaz went to see Mr Afzal at his family-run business, the E20 minicab offices in Stratford Broadway, east London.

Mr Patel said: "He was in relatively high spirits because he had not seen his girlfriend for some time.

PA

In court: Riaz is on trial at the Old Bailey

"He sent his friends away so they could be alone. He hoped he could persuade her that they had a meaningful future together.

"Nargis Riaz for her part hoped that that would be their last meeting because her true boyfriend at the time, Gulam Chowdhury, would make sure it was.

"They were alone as planned when Gulam Chowdhury stormed in and without warning or provocation vaulted the reception counter and in a frenzied and savage attack stabbed repeatedly the helpless Mohammed Afzal.

"He had no chance. Having been stabbed 20 times he promptly bled to death."

Riaz was present at the start of the attack and waited outside until Chowdhury had fled the scene before raising the alarm, the court heard.